Systems and methods for retraction of a packer assembly of an annular blowout preventer

ABSTRACT

A system for an annular blowout preventer (BOP) includes a piston, a packer assembly, and a connector assembly. The connector assembly includes a linkage, wherein a first end portion of the linkage is configured to contact and couple to the piston and a second end portion of the linkage is configured to contact and couple to the packer assembly.

BACKGROUND

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

An annular blowout preventer (BOP) is installed on a wellhead to seal and control an oil and gas well during drilling operations. A drill string may be suspended inside the oil and gas well from a rig through the annular BOP into the wellbore. During drilling operations, a drilling fluid is delivered through the drill string and returned up through an annulus between the drill string and a casing that lines the wellbore. In the event of a rapid invasion of formation fluid in the annulus, commonly known as a “kick,” the annular BOP may be actuated to seal the annulus and to control fluid pressure in the wellbore. In this way, the annular BOP may protect well equipment disposed above the annular BOP.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying figures in which like characters represent like parts throughout the figures, wherein:

FIG. 1 is a block diagram of a mineral extraction system, in accordance with an embodiment of the present disclosure;

FIG. 2 is a cross-sectional side view of an embodiment of an annular BOP that may be used in the mineral extraction system of FIG. 1, wherein the annular BOP includes multiple cables coupled to a packer, and the annular BOP is in an open position;

FIG. 3 is a cross-sectional side view of the annular BOP of FIG. 2, wherein the annular BOP is in a closed position;

FIG. 4 is a cross-sectional side view of an embodiment of the annular BOP that may be used in the mineral extraction system of FIG. 1, wherein the annular BOP includes the multiple cables coupled to multiple inserts, and the annular BOP is in the open position;

FIG. 5 is a cross-sectional side view of the annular BOP of FIG. 3, wherein the annular BOP is in the closed position;

FIG. 6 is a cross-sectional side view of an embodiment of the annular BOP that may be used in the mineral extraction system of FIG. 1, wherein the annular BOP includes multiple rods coupled to the multiple inserts, and the annular BOP is in the open position;

FIG. 7 is a cross-sectional side view of the annular BOP of FIG. 4, wherein the annular BOP is in the closed position;

FIG. 8 is a side view of an embodiment of one of the multiple inserts of FIGS. 6 and 7;

FIG. 9 is a cross-sectional side view of an embodiment of the annular BOP that may be used in the mineral extraction system of FIG. 1, wherein the annular BOP includes a normally-closed packer assembly, and the annular BOP is in the closed position;

FIG. 10 is a cross-sectional side view of the annular BOP of FIG. 9, wherein the annular BOP is in the open position;

FIG. 11 is a cross-sectional side view of an embodiment of the annular BOP that may be used in the mineral extraction system of FIG. 1, wherein the annular BOP includes multiple rods coupled to respective radially-outer surfaces of multiple inserts, and the annular BOP is in the open position; and

FIG. 12 is a cross-sectional side view of the annular BOP of FIG. 11, wherein the annular BOP is in the closed position.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present disclosure will be described below. These described embodiments are only exemplary of the present disclosure. Additionally, in an effort to provide a concise description of these exemplary embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

The present embodiments are generally related to annular blowout preventers (BOPs). In particular, the present embodiments are generally directed to a retraction system for annular BOPs. The retraction system may include a connector assembly with a linkage that extends between and couples a piston of the annular BOP to at least one of a packer of the packer assembly of the annular BOP or an insert of the packer assembly of the annular BOP. For example, the retraction system may include at least one cable (e.g., wire; bendable or flexible cable) that extends between and couples the piston to the packer. In some embodiments, the retraction system may include at least one cable that extends between and couples the piston to at least one of the inserts. In some embodiments, the retraction system may include at least one rod (e.g., rigid rod or bar) that extends between and couples the piston to at least one of the inserts.

The retraction system may facilitate retraction (e.g., withdrawal) of the packer assembly from a central bore of the annular BOP to thereby facilitate transition of the annular BOP from a closed position to an open position. In some embodiments, the retraction system may be used with a normally-closed packer assembly that is configured to seal the central bore of the annular BOP as a default position (e.g., default configuration; resting position or configuration). Then, the retraction system may be operated to retract the packer assembly from the central bore to thereby cause the annular BOP to transition from the closed position to the open position. Such a configuration may enable the annular BOP to be in the closed position as the default position to protect equipment positioned above the annular BOP and to be in the open position at certain times and/or during certain operations.

While the disclosed embodiments are described in the context of a drilling system and drilling operations to facilitate discussion, it should be appreciated that the annular BOP may be adapted for use in other contexts and other operations. For example, the annular BOP may be used in a pressure control equipment (PCE) stack that is coupled to and/or positioned vertically above a wellhead during various intervention operations (e.g., inspection or service operations), such as wireline operations in which a tool supported on a wireline is lowered through the PCE stack to enable inspection and/or maintenance of a well. In such cases, the annular BOP may be in the closed position (e.g., to seal about the wireline extending through the PCE stack) to isolate the environment, as well as other surface equipment, from pressurized fluid within the well. In the present disclosure, a conduit may be any of a variety of tubular or cylindrical structures, such as a drill string, wireline, Streamline™, slickline, coiled tubing, or other spoolable rod.

With the foregoing in mind, FIG. 1 is a block diagram of an embodiment of a mineral extraction system 10. The mineral extraction system 10 may be configured to extract various minerals and natural resources, including hydrocarbons (e.g., oil and/or natural gas), from the earth, or to inject substances into the earth. The mineral extraction system 10 may be a land-based system (e.g., a surface system) or an offshore system (e.g., an offshore platform system). A BOP assembly 16 is mounted to a wellhead 18, which is coupled to a mineral deposit 25 via a wellbore 26. The wellhead 18 may include any of a variety of other components such as a spool, a hanger, and a “Christmas” tree. The wellhead 18 may return drilling fluid or mud to the surface 12 during drilling operations, for example. Downhole operations are carried out by a conduit 24 that extends through the BOP assembly 16, through the wellhead 18, and into the wellbore 26.

To facilitate discussion, the BOP assembly 16 and its components may be described with reference to an axial axis or direction 30, a radial axis or direction 32, and a circumferential axis or direction 34. The BOP assembly 16 may include one or more annular BOPs 42. A central bore 44 (e.g., flow bore) extends through the one or more annular BOPs 42. As discussed in more detail below, at least one of the annular BOPs 42 may include a retraction system that has a connector assembly that couples a piston to a packer assembly (e.g., to a packer and/or an insert of the packer assembly). The retraction system may facilitate retraction of the packer assembly from the central bore 44 of the annular BOP 42. Thus, the retraction system may facilitate transition of the annular BOP 42 from a closed position in which the packer assembly blocks a fluid flow through the central bore 44 (e.g., seals an annulus about the conduit 24 disposed in the central bore 44; seals the central bore 44) to an open position in which the packer assembly is withdrawn from the central bore 44 (e.g., does not block the fluid flow through the central bore 44; does not seal the annular or the central bore 44).

FIGS. 2 and 3 each show a cross-sectional side view of an embodiment of the annular BOP 42 that may be used in the system 10 of FIG. 1. In FIG. 2, the annular BOP 42 is in an open position 50 (e.g., open configuration). In FIG. 3, the annular BOP 42 is in a closed position 52 (e.g., closed configuration). In the open position 50, the annular BOP 42 may enable fluid flow through the central bore 44 of the annular BOP 42. In the closed position 52, the annular BOP 42 may block fluid flow through the central bore 44 of the annular BOP 42.

As shown, the annular BOP 42 includes a housing 54 (e.g., annular housing) having a body 56 (e.g., body portion) and a top 58 (e.g., top portion) coupled to the body 56. A packer assembly 62 (e.g., annular packer assembly) within the housing 54 may include a packer 64 (e.g., annular packer; packing element) and multiple inserts 66. The packer 64 may be a flexible component (e.g., elastomer) and the multiple inserts 66 may be rigid components (e.g., metal or metal alloy). The multiple inserts 66 may extend axially through the packer 64 and may be positioned at discrete circumferential locations about the packer 64.

The annular BOP 42 may also include a piston 68 (e.g., annular piston) within the housing 54. An adapter 70 (e.g., annular adapter) may be positioned between the body 56 and the top 58, and various seals 72 (e.g., annular seals) may be provided in the body 56, the top 58, the piston 68, and/or the adapter 70 to seal spaces 74, 76 (e.g., annular spaces) from the central bore 44 and from one another.

The annular BOP 42 further includes a retraction system 80. The retraction system 80 may include a connector assembly 82 that connects or couples the packer assembly 62 to the piston 68. In the illustrated embodiment, the connector assembly 82 includes multiple cables 84 (e.g., wires; flexible or bendable cables; linkage). Each cable 84 includes a first end portion 86 that contacts and/or is coupled to the piston 68 and a second end portion 88 that contacts and/or is coupled to the packer 64. For example, the first end portion 86 may be fastened to the piston 68 (e.g., via a bonding agent, a weld, and/or a mechanical fastener), and the second end portion 88 may be fastened to the packer 64 (e.g., via a bonding agent and/or a mechanical fastener) and/or embedded in the packer 64 (e.g., embedded in and surrounded by the elastomer of the packer 64). In some embodiments, the first end portion 86 may be pivotally coupled (e.g., via a pivot) to the piston 68.

In operation, the piston 68 is configured to move relative to the housing 54 in the axial direction 30. For example, a fluid (e.g., a liquid and/or gas) may be provided to the space 76 via a first fluid conduit 100 to drive the piston 68 upward in the axial direction 30, as shown by arrow 102 in FIG. 2. As the piston 68 moves upward, the piston 68 drives the packer assembly 62 upward. For example, an axially-facing surface 104 (e.g., packer-contacting surface, top surface, upper surface, or annular surface) of the piston 68 may apply an upward force against an axially-facing surface 106 (e.g., piston-contacting surface, bottom surface, lower surface, or annular surface) of the packer assembly 62, driving the packer assembly 62 upward. When driven upward by the piston 68, the packer assembly 62 may move upward and inward within the top 60 until the packer 64 seals around the conduit 24 extending through the central bore 44 or closes off the central bore 44, thereby causing the annular BOP 42 to be in the closed position 52.

A second fluid conduit 108 is configured to provide a fluid (e.g., a liquid and/or gas) to the space 74 to drive the piston 68, as well as the cable 84 and the packer assembly 62 coupled thereto, downward. Because the cable 84 is coupled to both the packer 64 and the piston 68, the cable 84 may exert a force on the packer assembly 62 that drives and/or pulls the packer assembly 62 downward as the piston 68 moves downward (e.g., the packer assembly 62 and the piston 68 move downward together). As the packer assembly 62 moves downward, the packer assembly 62 may also expand and/or move outwardly within the top 60 (e.g., due to a curvature of the top 60). In this way, the packer assembly 62 may be retracted (e.g., withdrawn or pulled) from the central bore 44 and may cause the annular BOP 42 to move into the open position 50.

Without the cable 84, at least a portion of the packer assembly 62 (e.g., a larger portion as compared to the present embodiments that have the cable 84) may remain within the central bore 44. It should be appreciated that the piston 68 and associated components (e.g., the spaces 74, 76; the fluid conduits 100, 108; an electronic controller having a processor and memory that coordinates the delivery of the fluid to the spaces 74, 76) that cause adjustment of the connector assembly 82 may be considered part of the retraction system 80.

It should also be appreciated that the annular BOP 42 may include any number of cables 84. For example, the annular BOP 42 may include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more cables 84 positioned at discrete circumferential locations of the packer assembly 62 and the piston 68 (e.g., evenly or unevenly spaced along the circumferential axis 34). As shown, each cable 84 may be coupled to a center portion 110 of the packer 64. The center portion 110 may be approximately midway between a radially-inner surface (e.g., innermost surface; annular surface) and a radially-outer surface (e.g., outermost surface; annular surface) of the packer 64 and/or approximately midway between an axially-upper surface (e.g., uppermost surface; annular surface) and an axially-lower surface (e.g., lowermost surface; annular surface; the axially-facing surface 106) of the packer 64. This may enable the cable 84 to exert the force at the center portion 110 of the packer 64, which may in turn facilitate withdrawal of the packer assembly 62 from the central bore 44 (e.g., as opposed to coupling the cable 84 to the axially-facing surface 106 or to some other exterior surface or portion of the packer assembly 62). Furthermore, as shown, each cable 84 may be coupled to an axially-upper surface (e.g., uppermost surface; annular surface; the axially-facing surface 104) of the piston 68, which may contact the packer assembly 62 in the open position 50, the closed position 52, or both.

It should be appreciated that the cables 84 may be coupled to the packer 64 at any suitable portion of the packer 64 and may be coupled to the piston 68 at any suitable portion of the piston 68. For example, the cable 84 may be couple to the packer 64 at the axially-facing surface 106 of the packer assembly 62, at the radially-outer surface of the packer assembly 62, or at some other portion of the packer assembly 62 and/or the packer 64. Furthermore, in some embodiments, the packer assembly 62 and/or the packer 64 may be coupled to the piston 68 without the cable 84, such as via a linkage that includes a bonding agent (e.g., that bonds the surfaces 104, 106 together), a weld (e.g., that welds the surfaces 104, 106 together), and/or a mechanical fastener (e.g., that extends between and contacts the surfaces 104, 106 to join the packer assembly 62 to the piston 68).

Additionally or alternatively the connector assembly 82 may include one or more cables 84 coupled to the inserts 66. FIGS. 4 and 5 each show a cross-sectional side view of an embodiment of the annular BOP 42 that may be used in the system 10 of FIG. 1, wherein multiple cables 84 are coupled to the inserts 66 of the packer assembly 62. In FIG. 4, the annular BOP 42 is in the open position 50. In FIG. 5, the annular BOP 42 is in the closed position 52.

As shown, each cable 84 may include the first end portion 86 that contacts and/or is coupled to the piston 68 and the second end portion 88 that contacts and/or is coupled to the insert 66. For example, the first end portion 86 may be fastened to the piston 68, and the second end portion 88 may be fastened to the insert 66 (e.g., via a bonding agent, a weld, and/or a mechanical fastener). In some embodiments, the first end portion 86 may be pivotally coupled (e.g., via a pivot) to the piston 68 and/or the second end portion 88 may be pivotally coupled to the insert 66.

In response to the fluid being provided to the space 76 via the first fluid conduit 100, the piston 68 and the packer assembly 62 may move upward in the axial direction 30. When driven upward, the packer assembly 62 may move upward and inward within the top 60 until the packer 64 seals around the conduit 24 extending through the central bore 44 or closes off the central bore 44, thereby causing the annular BOP 42 to be in the closed position 52. In response to the fluid being provided to the space 74 via the second fluid conduit 108, the piston 68 and the packer assembly 62 may move downward. In particular, the cable 84 may exert a force on the packer assembly 62 that drives and/or pulls the packer assembly 62 downward as the piston 68 moves downward (e.g., the packer assembly 62 and the piston 68 move downward together). As the packer assembly 62 moves downward, the packer assembly 62 may also expand and/or move outwardly within the top 60 (e.g., due to a curvature of the top 60). In this way, the packer assembly 62 may be retracted (e.g., withdrawn or pulled) from the central bore 44 and may cause the annular BOP 42 to move into the open position 50.

Without the cable 84, at least a portion of the packer assembly 62 (e.g., a larger portion as compared to the present embodiments that have the cable 84) may remain within the central bore 44. It should be appreciated that the annular BOP 42 may include any number of cables 84. For example, the annular BOP 42 may include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more cables 84 positioned at discrete circumferential locations of the packer assembly 62 and the piston 68 (e.g., evenly or unevenly spaced along the circumferential axis 34).

As shown, each cable 84 may be coupled to a radially-outer surface 112 (e.g., curved surface; annular surface) of the insert 66. In some embodiments, each cable 84 may be coupled to the radially-outer surface 112 of the insert 66 that is exposed (e.g., uncovered by the packer 64) in the open position 50, the closed position 52, or both. Furthermore, the cable 84 may be coupled to a center portion 114 of the radially-outer surface 112 that is approximately midway between an axially-upper end (e.g., uppermost end portion) and an axially-lower surface (e.g., lowermost end portion) of the insert 66. This may enable the cable 84 to exert the force at the radially-outer surface 112 and at the center portion 114 of the insert 66, which may in turn facilitate withdrawal of the packer assembly 62 from the central bore 44 (e.g., as opposed to coupling the cable 84 to the axially-lower surface or to some other surface or portion of the insert 66). Furthermore, as shown, each cable 84 may be coupled to a radially-outer surface (e.g., radially-outermost surface; annular surface) and/or an axially-upper surface (e.g., uppermost surface; annular surface; the axially-facing surface 104) of the piston 68 that may contact the packer assembly 62 in the open position 50, the closed position 52, or both. Thus, in the illustrated embodiment, the cable 84 is positioned between a radially-inner surface of the housing 54 (e.g., a curved surface of the top 58) and a radially-outer surface of the packer assembly 62, and the cable 84 generally wraps around a portion of the packer assembly 62.

However, it should be appreciated that the cables 84 may be coupled to the insert 66 at any suitable portion of the insert 66 and may be coupled to the piston 68 at any suitable portion of the piston 68. For example, the cable 84 may be couple to the insert 66 at a portion of the insert 66 that is embedded within the packer 64 or at some other portion of the insert 66. Furthermore, the annular BOP 42 may have a structure in which the insert 66 and the piston 68 are in contact with one another. In some such cases, the insert 66 and the piston 68 may be coupled to one another without the cable 84, such as via a linkage that includes a bonding agent (e.g., that bonds surfaces of the insert 66 and the piston 68 together), a weld (e.g., that welds the surfaces of the insert 66 and the piston 68 together), and/or a mechanical fastener (e.g., that extends between and contacts the surfaces of the insert 66 and the piston 68 to join the packer assembly 62 to the piston 68).

The connector assembly 82 may have any of a variety of other configurations. For example, FIGS. 6 and 7 each show a cross-sectional side view of an embodiment of the annular BOP 42 that may be used in the system 10 of FIG. 1, wherein the connector assembly 82 includes multiple rods 150 (e.g., rigid rods; linkage) coupled to the inserts 66 of the packer assembly 62. In FIG. 6, the annular BOP 42 is in the open position 50. In FIG. 7, the annular BOP 42 is in the closed position 52.

As shown, each rod 150 includes a first end portion 152 that contacts and/or is coupled to the piston 68 and a second end portion 154 that contacts and/or is coupled to the insert 66. For example, the first end portion 152 may be fastened to the piston 68, and the second end portion 154 may be fastened to the insert 66. In response to the fluid being provided to the space 76 via the first fluid conduit 100, the piston 68 and the packer assembly 62 may move upward in the axial direction 30. When driven upward, the packer assembly 62 may move upward and inward within the top 60 until the packer 64 seals around the conduit 24 extending through the central bore 44 or closes off the central bore 44, thereby causing the annular BOP 42 to be in the closed position 52. In response to the fluid being provided to the space 74 via the second fluid conduit 108, the piston 68 and the packer assembly 62 may move downward. In particular, the rod 150 may exert a force on the packer assembly 62 that drives and/or pulls the packer assembly 62 downward as the piston 68 moves downward (e.g., the packer assembly 62 and the piston 68 move downward together). As the packer assembly 62 moves downward, the packer assembly 62 may also expand and/or move outwardly within the top 60 (e.g., due to a curvature of the top 60). In this way, the packer assembly 62 may be retracted (e.g., withdrawn or pulled) from the central bore 44 and may cause the annular BOP 42 to move into the open position 50.

Without the rod 150, at least a portion of the packer assembly 62 (e.g., a larger portion as compared to the present embodiments that have the rod 150) may remain within the central bore 44. It should be appreciated that the annular BOP 42 may include any number of rods 150. For example, the annular BOP 42 may include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more rods 150 positioned at discrete circumferential locations of the packer assembly 62 and the piston 68 (e.g., evenly or unevenly spaced along the circumferential axis 34). As shown, each rod 150 may be coupled to a center portion 156 of the insert 66. The center portion 156 may be approximately midway between a radially-inner surface (e.g., innermost surface; annular surface) and a radially-outer surface (e.g., outermost surface; annular surface) of the insert 66 and/or approximately midway between an axially-upper end (e.g., uppermost end portion) and an axially-lower end (e.g., lowermost end portion) of the insert 66. The center portion 156 may be embedded within the packer 64, and thus, the rod 150 may extend through the packer 64. This may enable the rod 150 to exert the force at the center portion 156 of the insert 166, which may in turn facilitate withdrawal of the packer assembly 62 from the central bore 44 (e.g., as opposed to coupling the rod 150 to some other surface or portion of the insert 66). Furthermore, as shown, each rod 150 may extend from an axially-upper surface (e.g., uppermost surface; annular surface; the axially-facing surface 104) of the piston 68, which may contact the packer assembly 62 in the open position 50, the closed position 52, or both. However, it should be appreciated that the rod 150 may be coupled to the insert 66 at any suitable portion of the insert 66 and may be coupled to the piston 68 at any suitable portion of the piston 68.

To enable the packer assembly 62 to move upward and inward into the central bore 44 (e.g., inward relative to the piston 68), at least the second end portion 154 of the rod 150 may be pivotally (e.g., rotatably) coupled to the insert 66 via a pivot 158 (e.g., pivot assembly; pin). Thus, as the piston 68 drives the packer assembly 62 upward, the insert 66 may rotate in a direction of arrow 160 about the pivot 158 (e.g., relative to the rod 150, the piston 68, and/or the housing 54). Similarly, as the piston 68 and the rod 150 pull the packer assembly 62 downward, the insert 66 may rotate in a direction opposite of the arrow 160 about the pivot 158. This configuration enables the piston 68 to move along the axial axis 30 and enables the packer assembly 62 to move upward and inward into the central bore 44, while the piston 68 and the packer assembly 62 are coupled to one another via the connector assembly 82.

In some embodiments, at least the first end portion 152 of the rod 150 may be pivotally coupled to the piston 68 via a pivot 159 (e.g., pivot assembly; pin). In operation, as the piston 68 drives the packer assembly 62 upward, the rod 150 may rotate in a direction of arrow 161 about the pivot 159 (e.g., relative to the rod 150, the piston 68, and/or the housing 54). Similarly, as the piston 68 and the rod 150 pull the packer assembly 62 downward, the rod 150 may rotate in a direction opposite of the arrow 161 about the pivot 159. In some embodiments, as shown, the second end portion 154 of the rod 150 may be pivotally coupled to the insert 66 via the pivot 158, and the first end portion 152 of the rod 150 may be pivotally coupled to the piston 68 via the pivot 159. However, in some embodiments, at least one of the pivots 158, 159 may be replaced by a fixed (e.g., non-rotatable) connection. For example, each rod 150 may be supported within (e.g., threaded into) a recess formed in the axially-upper surface of the piston 68.

With reference to FIG. 8, the connector assembly 82 may be coupled to a side surface 162 (e.g., circumferentially-facing surface) of the insert 66. For example, the pivot 158 may be a pin that extends into the insert 66 from the side surface 162 and that enables rotation of the insert 66 relative to the rod 150. Thus, in operation, the insert 66 may rotate relative to the rod 150 in the direction of the arrow 160 and in the direction opposite of the arrow 160 as the piston 68 moves along the axial axis 30 to adjust the annular BOP 42 between the open position 50 and the closed position 52 (FIGS. 6 and 7). The connector assembly 82 may also be coupled to the piston 68 via the pivot 159, which may include a pin supported on a bracket, and which enables rotation of the rod 150 relative to the piston 68. Thus, in operation, the rod 150 may rotate relative to the piston 68 in the direction of arrow 161 and in the direction opposite of the arrow 161 as the piston 68 moves along the axial axis 30 to adjust the annular BOP 42 between the open position 50 and the closed position 52 (FIGS. 6 and 7).

FIG. 9 is a cross-sectional side view of an embodiment of the annular BOP 42 that may be used in the system 10 of FIG. 1, wherein the annular BOP 42 includes a normally-closed packer assembly 200 (e.g., annular packer assembly) and is in the closed position 52. FIG. 10 is a cross-sectional side view of the annular BOP 42 of FIG. 9, wherein the annular BOP 42 is in the open position 50.

In some embodiments, the retraction system 80 may be used with the normally-closed packer assembly 200 that is configured (e.g., shaped; molded) to seal the central bore 44 of the annular BOP 42 as a default position (e.g., default configuration; a resting position or configuration). That is, in the absence of external downward forces from the retraction system 80, a shape (e.g., a molded shape) of the normally-closed packer assembly 200 may cause the normally-closed packer assembly 200 to extend into the central bore 44, block the fluid flow through the central bore 44, seal against the conduit 24, and/or otherwise seal the central bore 44 (e.g., in the absence of the conduit 24) to place the annular BOP 42 in the closed position 52. Thus, while the retraction system 80 may include the piston 68, the piston 68 may not drive the normally-closed packer assembly 200 to the position illustrated in FIG. 9 to adjust the annular BOP 42 to the closed position 52. Instead, the piston 68 may merely support the normally-closed packer assembly 200 while the normally-closed packer assembly 200 is in the default position.

In some such cases, the normally-closed packer assembly 200 may have a shape that does include a central opening at manufacture, but the central opening is closed upon installation within the annular BOP 42, and/or in the default position. For example, opposing radially-inner walls of the normally-closed packer assembly 200 may contact one another and seal against one another at manufacture and/or upon installation within the annular BOP 42. Then, the normally-closed packer assembly 200 may be selectively and/or temporarily driven or pulled by the retraction system 80 as disclosed herein, which may cause the radially-inner walls of the normally-closed packer assembly 200 to separate from one another to form the central opening (e.g., the normally-closed packer assembly 200 may become annular) that may align with the central bore 44 to enable passage of the conduit 24.

In particular, the retraction system 80 may be operated to retract the normally-closed packer assembly 200 to thereby cause the annular BOP 42 to transition from the closed position 52 of FIG. 9 to the open position 50 of FIG. 10. For example, a fluid conduit 202 is configured to provide a fluid (e.g., a liquid and/or gas) to a space 204 (e.g., annular space) to drive the piston 68, as well as the rod 150 and the normally-closed packer assembly 200 coupled thereto, downward. Because the rod 150 coupled to both the insert 66 and the piston 68, the rod 150 may exert a force on the normally-closed packer assembly 200 that drives and/or pulls the normally-closed packer assembly 200 downward as the piston 68 moves downward (e.g., the normally-closed packer assembly 200 and the piston 68 move downward together). As the normally-closed packer assembly 200 moves downward, the normally-closed packer assembly 200 may also expand and/or move outwardly within the top 60 (e.g., due to a curvature of the top 60). In this way, the normally-closed packer assembly 200 may be retracted (e.g., withdrawn or pulled) from the central bore 44 and may cause the annular BOP 42 to move into the open position 50. Such a configuration may enable the annular BOP 42 to be in the closed position 52 as the default position to protect equipment positioned above the annular BOP 42 and to be in the open position 50 only at certain times and/or during certain operations (e.g., temporarily; upon an input by an operator; via an electronic controller that instructs the provision of the fluid to adjust the normally-closed packer assembly 200, such as to enable the conduit 24 to extend through the central bore 44). In this way, the retraction system 80 may enable use of the normally-closed packer assembly 200 within the annular BOP 42.

As shown, the normally-closed packer assembly 200 may include a packer 206 (e.g., annular packer) and multiple inserts 208. It should be appreciated that the annular BOP 42 may include any number of rods 150. For example, the annular BOP 42 may include 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more rods 150 positioned at discrete circumferential locations of the normally-closed packer assembly 200 and the piston 68 (e.g., evenly or unevenly spaced along the circumferential axis 34). While the illustrated embodiment includes the rod 150 of FIGS. 6-8 to facilitate discussion, it should be appreciated that the cable 84 of FIGS. 2-5 may be utilized in addition to or as an alternative to the rod 150.

Furthermore, the normally-closed packer assembly 200 may be driven out of the central bore 44 or may be adjusted to otherwise accommodate the conduit 24 in other ways. For example, the normally-closed packer assembly 200 may seal the central bore 44 in the absence of the conduit 24 and/or in the absence of the force from the retraction system 80. Then, the conduit 24 may be driven or pushed into the central bore 44 (e.g., during stripping operations), and the conduit 24 may push the normally-closed packer assembly 200 radially-outwardly and/or downwardly (and, in some cases, the rod 150 and the piston 68 downwardly) so that the conduit 24 may pass through the normally-closed packer assembly 200. In some embodiments, the normally-closed packer assembly 200 may not seal the central bore 44 in the absence of the conduit 24, but instead may seal against the conduit 24 as the default position. In such cases, the normally-closed packer assembly 200 may then be driven away from the conduit 24 and out of the central bore 44 to adjust the annular BOP 42 to the open position 50.

It is envisioned that the retraction system 80 disclosed herein may be adapted for use in any of a variety of annular BOPs 42 having any of a variety of structural features. For example, FIGS. 11 and 12 each show a cross-sectional side view of an embodiment of the annular BOP 42 that may be used in the system 10 of FIG. 1, wherein the connector assembly 82 includes multiple rods 150 coupled to respective radially-outer surfaces 220 of inserts 222 of a normally-closed packer assembly 224. In FIG. 11, the annular BOP 42 is in the open position 50. In FIG. 12, the annular BOP 42 is in the closed position 52.

The normally-closed packer assembly 224 may include the inserts 222 and a packer 226, and the normally-closed packer assembly 224 may be configured (e.g., shaped; molded) to seal the central bore 44 of the annular BOP 42 as a default position (e.g., default configuration; a resting position or configuration). The normally-closed packer assembly 224 may include any of the features and operational characteristics of the normally-closed packer assembly 200 of FIGS. 9 and 10. Additionally, while the illustrated embodiment includes the rod 150 of FIGS. 6-10 to facilitate discussion, it should be appreciated that the cable 84 of FIGS. 2-5 may be utilized in addition to or as an alternative to the rod 150.

The retraction system may also be adapted for use in annular BOPs having iris-style inserts (e.g., that rotate radially-inwardly as the annular BOP moves from the open position to the closed position). Accordingly, it should be understood that the annular BOP of FIGS. 1-10 is merely exemplary and are not intended to be limiting. For example, the housing, the packer, and/or the multiple inserts may have various other shapes and configurations.

It should also be understood that any of the various components, features, or characteristics illustrated or described above with respect to FIGS. 1-10 may be combined. For example, the annular BOP may include the cables and/or the rods. Furthermore, the annular BOP may include the cables coupled to the packer and/or to the inserts. Any of the disclosed embodiments may enable the annular BOP to be positively opened via the retraction system and/or to be normally closed to thereby protect components positioned above the annular BOP, among other advantages. For example, the annular BOP and the retraction system of FIGS. 11 and 12 may be utilized without a normally-closed packer assembly (i.e., the packer assembly may not be molded to be normally-closed as a default position). Similarly, any of the annular BOPs in FIGS. 2-8 may be utilized with a normally-closed packer assembly (i.e., the packer assembly may be molded to be normally-closed as a default position).

While the disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims.

The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f). 

1. A system for an annular blowout preventer (BOP), comprising: an annular piston; a packer assembly; and a connector assembly comprising a linkage, wherein a first end portion of the linkage is configured to contact and couple to the annular piston and a second end portion of the linkage is configured to contact and couple to the packer assembly.
 2. The system of claim 1, wherein the linkage comprises a cable.
 3. The system of claim 2, wherein the second end portion is embedded in a packer of the packer assembly.
 4. The system of claim 2, wherein the second end portion is coupled to an insert of the packer assembly.
 5. The system of claim 1, wherein the linkage comprises a rigid rod.
 6. The system of claim 5, wherein the second end portion is coupled to an insert of the packer assembly.
 7. The system of claim 5, wherein the second end portion is configured to rotatably couple to an insert of the packer assembly.
 8. The system of claim 1, wherein the second end portion is coupled to a center portion of the packer assembly.
 9. The system of claim 1, wherein the connector assembly comprises a plurality of additional linkages spaced circumferentially about the packer assembly, wherein a respective first end portion of each of the plurality of additional linkages is configured to contact and couple to the annular piston and a respective second end portion of each of the plurality of additional linkages is configured to contact and couple to the packer assembly.
 10. The system of claim 1, wherein the connector assembly is configured to exert a force on the packer assembly to withdraw the packer assembly from a central bore of the annular BOP as the annular piston moves in a first direction along an axial axis of the annular BOP.
 11. The system of claim 1, wherein the packer assembly comprises a normally-closed packer assembly that comprises a molded shape that causes the normally-closed packer assembly to seal a central bore of the annular BOP in absence of an external downward force from the connector assembly.
 12. An annular blowout preventer (BOP), comprising: a housing; an annular piston positioned within the housing; a packer assembly positioned within the housing, wherein the packer assembly comprises a packer and a plurality of inserts; and a connector assembly positioned within the housing, wherein the connector assembly is configured to couple the annular piston and the packer assembly to one another and to exert a force on the packer assembly to withdraw the packer assembly from a central bore of the annular BOP as the annular piston moves in a first direction along an axial axis of the annular BOP.
 13. The annular BOP of claim 12, wherein the connector assembly comprises a linkage, a first end portion of the linkage is configured to contact and couple to the annular piston, and a second end portion of the linkage is configured to contact and couple to the packer assembly.
 14. The annular BOP of claim 12, wherein a portion of the connector assembly is embedded in the packer.
 15. The annular BOP of claim 12, wherein a portion of the connector assembly contacts and is coupled to at least one insert of the plurality of inserts.
 16. The annular BOP of claim 12, wherein the connector assembly comprises a rigid rod that is coupled to the annular piston and to at least one insert of the plurality of inserts.
 17. The annular BOP of claim 16, wherein the rigid rod is rotatably coupled to the at least one insert of the plurality of inserts.
 18. The annular BOP of claim 12, wherein the packer assembly comprises a normally-closed packer assembly that comprises a molded shape that causes the normally-closed packer assembly to seal the central bore of the annular BOP in absence of the force.
 19. A method of operating an annular blowout preventer (BOP), the method comprising: adjusting an annular piston of the annular BOP in a first axial direction; and withdrawing a packer assembly of the annular BOP from a central bore of the annular BOP via a force exerted on the packer assembly by a connector assembly that is coupled to the annular piston and the packer assembly.
 20. The method of claim 19, wherein the packer assembly is a normally-closed packer assembly, and the method comprises transitioning the annular BOP from a closed position to an open position by adjusting the annular piston of the annular BOP in the first axial direction. 